diff options
Diffstat (limited to 'linux-user')
| -rw-r--r-- | linux-user/elfload.c | 7 | ||||
| -rw-r--r-- | linux-user/flatload.c | 2 | ||||
| -rw-r--r-- | linux-user/main.c | 2 | ||||
| -rw-r--r-- | linux-user/mmap.c | 49 | ||||
| -rw-r--r-- | linux-user/qemu.h | 1 | ||||
| -rw-r--r-- | linux-user/syscall.c | 67 | ||||
| -rw-r--r-- | linux-user/user-mmap.h | 1 |
7 files changed, 55 insertions, 74 deletions
diff --git a/linux-user/elfload.c b/linux-user/elfload.c index 861ec07abc..36e4026f05 100644 --- a/linux-user/elfload.c +++ b/linux-user/elfload.c @@ -1710,7 +1710,8 @@ static uint32_t get_elf_hwcap(void) #define MISA_BIT(EXT) (1 << (EXT - 'A')) RISCVCPU *cpu = RISCV_CPU(thread_cpu); uint32_t mask = MISA_BIT('I') | MISA_BIT('M') | MISA_BIT('A') - | MISA_BIT('F') | MISA_BIT('D') | MISA_BIT('C'); + | MISA_BIT('F') | MISA_BIT('D') | MISA_BIT('C') + | MISA_BIT('V'); return cpu->env.misa_ext & mask; #undef MISA_BIT @@ -3678,8 +3679,8 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info) * to mmap pages in this space. */ if (info->reserve_brk) { - abi_ulong start_brk = HOST_PAGE_ALIGN(info->brk); - abi_ulong end_brk = HOST_PAGE_ALIGN(info->brk + info->reserve_brk); + abi_ulong start_brk = TARGET_PAGE_ALIGN(info->brk); + abi_ulong end_brk = TARGET_PAGE_ALIGN(info->brk + info->reserve_brk); target_munmap(start_brk, end_brk - start_brk); } diff --git a/linux-user/flatload.c b/linux-user/flatload.c index 5efec2630e..8f5e9f489b 100644 --- a/linux-user/flatload.c +++ b/linux-user/flatload.c @@ -811,7 +811,7 @@ int load_flt_binary(struct linux_binprm *bprm, struct image_info *info) info->end_code = libinfo[0].start_code + libinfo[0].text_len; info->start_data = libinfo[0].start_data; info->end_data = libinfo[0].end_data; - info->start_brk = libinfo[0].start_brk; + info->brk = libinfo[0].start_brk; info->start_stack = sp; info->stack_limit = libinfo[0].start_brk; info->entry = start_addr; diff --git a/linux-user/main.c b/linux-user/main.c index dba67ffa36..556956c363 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -920,8 +920,6 @@ int main(int argc, char **argv, char **envp) fprintf(f, "page layout changed following binary load\n"); page_dump(f); - fprintf(f, "start_brk 0x" TARGET_ABI_FMT_lx "\n", - info->start_brk); fprintf(f, "end_code 0x" TARGET_ABI_FMT_lx "\n", info->end_code); fprintf(f, "start_code 0x" TARGET_ABI_FMT_lx "\n", diff --git a/linux-user/mmap.c b/linux-user/mmap.c index a5dfb56545..eb04fab8ab 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -263,7 +263,11 @@ static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, void *p = mmap(host_start, qemu_host_page_size, target_to_host_prot(prot), flags | MAP_ANONYMOUS, -1, 0); - if (p == MAP_FAILED) { + if (p != host_start) { + if (p != MAP_FAILED) { + munmap(p, qemu_host_page_size); + errno = EEXIST; + } return false; } prot_old = prot; @@ -310,8 +314,6 @@ static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, #endif abi_ulong mmap_next_start = TASK_UNMAPPED_BASE; -unsigned long last_brk; - /* * Subroutine of mmap_find_vma, used when we have pre-allocated * a chunk of guest address space. @@ -603,11 +605,26 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, goto fail; } - /* Validate that the chosen range is empty. */ - if ((flags & MAP_FIXED_NOREPLACE) - && !page_check_range_empty(start, last)) { - errno = EEXIST; - goto fail; + if (flags & MAP_FIXED_NOREPLACE) { + /* Validate that the chosen range is empty. */ + if (!page_check_range_empty(start, last)) { + errno = EEXIST; + goto fail; + } + + /* + * With reserved_va, the entire address space is mmaped in the + * host to ensure it isn't accidentally used for something else. + * We have just checked that the guest address is not mapped + * within the guest, but need to replace the host reservation. + * + * Without reserved_va, despite the guest address check above, + * keep MAP_FIXED_NOREPLACE so that the guest does not overwrite + * any host address mappings. + */ + if (reserved_va) { + flags = (flags & ~MAP_FIXED_NOREPLACE) | MAP_FIXED; + } } /* @@ -672,17 +689,25 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, /* map the middle (easier) */ if (real_start < real_last) { - void *p; + void *p, *want_p; off_t offset1; + size_t len1; if (flags & MAP_ANONYMOUS) { offset1 = 0; } else { offset1 = offset + real_start - start; } - p = mmap(g2h_untagged(real_start), real_last - real_start + 1, - target_to_host_prot(target_prot), flags, fd, offset1); - if (p == MAP_FAILED) { + len1 = real_last - real_start + 1; + want_p = g2h_untagged(real_start); + + p = mmap(want_p, len1, target_to_host_prot(target_prot), + flags, fd, offset1); + if (p != want_p) { + if (p != MAP_FAILED) { + munmap(p, len1); + errno = EEXIST; + } goto fail; } passthrough_start = real_start; diff --git a/linux-user/qemu.h b/linux-user/qemu.h index 802794db63..2046a23037 100644 --- a/linux-user/qemu.h +++ b/linux-user/qemu.h @@ -29,7 +29,6 @@ struct image_info { abi_ulong end_code; abi_ulong start_data; abi_ulong end_data; - abi_ulong start_brk; abi_ulong brk; abi_ulong reserve_brk; abi_ulong start_mmap; diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 95727a816a..7c2c2f6e2f 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -802,93 +802,52 @@ static inline int host_to_target_sock_type(int host_type) } static abi_ulong target_brk, initial_target_brk; -static abi_ulong brk_page; void target_set_brk(abi_ulong new_brk) { target_brk = TARGET_PAGE_ALIGN(new_brk); initial_target_brk = target_brk; - brk_page = HOST_PAGE_ALIGN(target_brk); } /* do_brk() must return target values and target errnos. */ abi_long do_brk(abi_ulong brk_val) { abi_long mapped_addr; - abi_ulong new_alloc_size; - abi_ulong new_brk, new_host_brk_page; + abi_ulong new_brk; + abi_ulong old_brk; /* brk pointers are always untagged */ - /* return old brk value if brk_val unchanged or zero */ - if (!brk_val || brk_val == target_brk) { - return target_brk; - } - /* do not allow to shrink below initial brk value */ if (brk_val < initial_target_brk) { - brk_val = initial_target_brk; + return target_brk; } new_brk = TARGET_PAGE_ALIGN(brk_val); - new_host_brk_page = HOST_PAGE_ALIGN(brk_val); + old_brk = TARGET_PAGE_ALIGN(target_brk); - /* brk_val and old target_brk might be on the same page */ - if (new_brk == TARGET_PAGE_ALIGN(target_brk)) { - /* empty remaining bytes in (possibly larger) host page */ - memset(g2h_untagged(new_brk), 0, new_host_brk_page - new_brk); + /* new and old target_brk might be on the same page */ + if (new_brk == old_brk) { target_brk = brk_val; return target_brk; } /* Release heap if necesary */ - if (new_brk < target_brk) { - /* empty remaining bytes in (possibly larger) host page */ - memset(g2h_untagged(new_brk), 0, new_host_brk_page - new_brk); - - /* free unused host pages and set new brk_page */ - target_munmap(new_host_brk_page, brk_page - new_host_brk_page); - brk_page = new_host_brk_page; + if (new_brk < old_brk) { + target_munmap(new_brk, old_brk - new_brk); target_brk = brk_val; return target_brk; } - /* We need to allocate more memory after the brk... Note that - * we don't use MAP_FIXED because that will map over the top of - * any existing mapping (like the one with the host libc or qemu - * itself); instead we treat "mapped but at wrong address" as - * a failure and unmap again. - */ - if (new_host_brk_page > brk_page) { - new_alloc_size = new_host_brk_page - brk_page; - mapped_addr = get_errno(target_mmap(brk_page, new_alloc_size, - PROT_READ|PROT_WRITE, - MAP_ANON|MAP_PRIVATE, 0, 0)); - } else { - new_alloc_size = 0; - mapped_addr = brk_page; - } - - if (mapped_addr == brk_page) { - /* Heap contents are initialized to zero, as for anonymous - * mapped pages. Technically the new pages are already - * initialized to zero since they *are* anonymous mapped - * pages, however we have to take care with the contents that - * come from the remaining part of the previous page: it may - * contains garbage data due to a previous heap usage (grown - * then shrunken). */ - memset(g2h_untagged(brk_page), 0, HOST_PAGE_ALIGN(brk_page) - brk_page); + mapped_addr = target_mmap(old_brk, new_brk - old_brk, + PROT_READ | PROT_WRITE, + MAP_FIXED_NOREPLACE | MAP_ANON | MAP_PRIVATE, + -1, 0); + if (mapped_addr == old_brk) { target_brk = brk_val; - brk_page = new_host_brk_page; return target_brk; - } else if (mapped_addr != -1) { - /* Mapped but at wrong address, meaning there wasn't actually - * enough space for this brk. - */ - target_munmap(mapped_addr, new_alloc_size); - mapped_addr = -1; } #if defined(TARGET_ALPHA) diff --git a/linux-user/user-mmap.h b/linux-user/user-mmap.h index 3fc986f92f..7265c2c116 100644 --- a/linux-user/user-mmap.h +++ b/linux-user/user-mmap.h @@ -26,7 +26,6 @@ abi_long target_mremap(abi_ulong old_addr, abi_ulong old_size, abi_ulong new_size, unsigned long flags, abi_ulong new_addr); abi_long target_madvise(abi_ulong start, abi_ulong len_in, int advice); -extern unsigned long last_brk; extern abi_ulong mmap_next_start; abi_ulong mmap_find_vma(abi_ulong, abi_ulong, abi_ulong); void mmap_fork_start(void); |